Did you use the Xbox? Remember that interface? Are you laughing? It was pretty bad, as was the first Xbox 360 one. Blades gave way to a mess of boxes, bringing us to the point we're at now. I'm sure you'll agree we're not at a good place now when it comes to Xbox 360's UI.
From what I've seen of the Xbox One interface, it seems that Microsoft has been listening to our gripes. I'd almost call the new one elegant. It's certainly clean and well-thought-out, and not unlike something you'd see on a mobile device....